I’m working on a Ford engine JTJA. After timing job the car won't start. On the crankshaft pulley there’s a metal ring with ONE window/notch, and the CKP sensor sits right next to that ring.

Problem is: When I first took it apart, that inner ring actually came loose from the pulley. I had no reference, so I put it back randomly. After that I locked the crank using the proper locking tool (which goes through that window), locked the cams, inserted the locking screw and made sure the 1st cylindersis at TDC, and basically did timing properly.

I’m not fully sure how this system works, and I’m trying to understand it correctly rather than assume anything. Currently engine cranks but does NOT start

Also worth mentioning that the window is slightly damaged (see image attached). I’m not sure if this affects the sensor reading

My questions:

1. How does this system actually work with a single window? Is the CKP sensor detecting that window as a reference event?

2. Is that window supposed to be in a very specific angular position relative to the crankshaft (not just for locking)?

3. If the metal ring was removed and reinstalled randomly, is there a defined way to re-index it correctly?

4. Could a slightly damaged window cause the ECU to reject the crank signal and prevent starting?

Any insight from someone familiar with this setup would be greatly appreciated.

First the sensor ring should not come loose from the pulley. The hole should align with the center of one of the 4 openings inside the pulley.



The fact that the timing ring came loose from the pulley is not a good sign. I suggest taking no risk and to just replace the pulley.

The crankshaft position sensor checks the crankshaft position in relation to the position of both camshafts. The crankshaft position sensor detects the opening inside the sensor ring. It is therefore crucial that the sensor ring is aligned correctly. If the position signal of the 3 sensors does not match the car will either not start or go into limp mode and generate a DTC code.




The crankshaft pulley is aligned using Ford special timing tool 303-1550. Note that this tool is only used to position the pulley. With the special timing tool in place the crankshaft pulley bolt must only be fastened "finger tight". The special tool must be removed before tightening the crankshaft pulley bolt to its final torque and angle.

After everything is aligned properly and the crankshaft pulley bolt is fully tightened all of the special timing tools must be removed and the crankshaft must be rotated exactly 2 revolutions. If everything is done correctly all timing tools should go into place.


Being a Fiesta ST 1.6 EcoBoost it is important to know that some tuners (for example Mountune on the MR230) use different camshaft timing. Using the standard camshaft timing tool on such a modified engine will result in the engine not starting.


Mountune MR230 camshaft timing tool.

I have seen before that people bought a modified Fiesta ST unknown of the specific modifications. After replacement of the timing belt the engine no longer started.

Thank you for the detailed answer.

A few important points:

• I do not have another pulley to compare with at the moment.

• The metal ring was not easy to reinstall and could only be put back in using force or heat. I reinstalled it by gently tapping it back in with a hammer until it was fully seated.

• The engine is not modified.

The real story behind the timing job is that the engine went through a full rebuild:
main bearings, rod bearings, piston rings, gaskets, head and block re-surfaced, and cylinder honing were all done.

At this point, I have basically ruled out the other common causes:
compression, air, fuel, and spark all seem to be present. That is why timing is the main thing left that I suspect.

I have a FOXWELL NT1009 diagnostic tool, and I already performed the camshaft relearn procedure.
However, it requires the engine to start and idle for 60 seconds, and I cannot complete that because the engine will not start.

Lastly, my pulley does not have the outer holes (green) like yours.
It only has the 4 inner holes (red), and I aligned the ring window to the center of one of those holes.

Any idea what can it be?

If you have come this far, you are not a beginner so I think you will understand this. You have compression so the cams and crank appear to be phased correctly so the belt is all right. What you need to know is at what crank angle BTDC the trigger event occurs. This should be published and I hope that you can google it. The holes are a red herring because you don't know where the window is supposed to be on the pulley. If I could get the disc off again, I would look for a trace of corrosion on the pulley face under a magnifying glass to try to establish a witness mark but if not, I would find the static timing of the engine and try to get the engine to that position by bringing number one to tdc with both valves closed and turning backwards to that point before realigning the pulley window onto the sensor. That ought to get you close enough to get a start. A bit of hunting on youtube for somebody who has done the job might give a clue if there is a picture of it all lined up.

The position of the sensor ring in relation to the pulley does not really matter in my opinion.

The pulley is keyless and balanced so it can basically be fit in any position. The only thing that matters is the position of the hole inside the sensor ring but that is correctly timed using the special timing tool.

It is completely different from for example the 1.0 EcoBoost where the pulley is deliberately unbalanced to compensate for engine vibrations. On the 1.0 EcoBoost the position of the pulley does matter.


Personally, I would start diagnosing the problem using a Ford specific diagnostic system. For example Forscan. In this case I would specifically look at the live data during cranking. The crankshaft position sensor should at least show a steady signal while cranking.

It would not be the 1st time that one of these crankshaft position sensors fails after being disassemblem/assembled.

2 hours ago, anon said:

If you have come this far, you are not a beginner so I think you will understand this. You have compression so the cams and crank appear to be phased correctly so the belt is all right. What you need to know is at what crank angle BTDC the trigger event occurs. This should be published and I hope that you can google it. The holes are a red herring because you don't know where the window is supposed to be on the pulley. If I could get the disc off again, I would look for a trace of corrosion on the pulley face under a magnifying glass to try to establish a witness mark but if not, I would find the static timing of the engine and try to get the engine to that position by bringing number one to tdc with both valves closed and turning backwards to that point before realigning the pulley window onto the sensor. That ought to get you close enough to get a start. A bit of hunting on youtube for somebody who has done the job might give a clue if there is a picture of it all lined up.

Great and advanced answer! but I actually think the window location is what matter (aligned using the alignment tool) since this is Hall Effect sensor..

1 hour ago, JW1982 said:

The position of the sensor ring in relation to the pulley does not really matter in my opinion.

The pulley is keyless and balanced so it can basically be fit in any position. The only thing that matters is the position of the hole inside the sensor ring but that is correctly timed using the special timing tool.

It is completely different from for example the 1.0 EcoBoost where the pulley is deliberately unbalanced to compensate for engine vibrations. On the 1.0 EcoBoost the position of the pulley does matter.


Personally, I would start diagnosing the problem using a Ford specific diagnostic system. For example Forscan. In this case I would specifically look at the live data during cranking. The crankshaft position sensor should at least show a steady signal while cranking.

It would not be the 1st time that one of these crankshaft position sensors fails after being disassemblem/assembled.

I will try to check for live data and also will test the sensor using multimeter..

3 minutes ago, Falcon93 said:

Great and advanced answer! but I actually think the window location is what matter (aligned using the alignment tool) since this is Hall Effect sensor..

I will try to check for live data and also will test the sensor using multimeter..

Which is why I wrote "-before realigning the pulley window onto the sensor." Perhaps I should have explained that it would be necessary to loosen the pulley first so that this could be achieved at the timing point the engine is now turned to.

On 4/6/2026 at 2:30 PM, JW1982 said:

The position of the sensor ring in relation to the pulley does not really matter in my opinion.

The pulley is keyless and balanced so it can basically be fit in any position. The only thing that matters is the position of the hole inside the sensor ring but that is correctly timed using the special timing tool.

It is completely different from for example the 1.0 EcoBoost where the pulley is deliberately unbalanced to compensate for engine vibrations. On the 1.0 EcoBoost the position of the pulley does matter.


Personally, I would start diagnosing the problem using a Ford specific diagnostic system. For example Forscan. In this case I would specifically look at the live data during cranking. The crankshaft position sensor should at least show a steady signal while cranking.

It would not be the 1st time that one of these crankshaft position sensors fails after being disassemblem/assembled.

After checking live data, I see that crank signal is OFF during the ignition attempt.

The camshafts position sensors values are also static.

Is it possible that the signal is invalid due to the ring malformed situation?

In the video you can see live data of the selected values during 2 ignition attempts:

Well, that sensor ring inside the pulley does definitely not look good and considering the damage it should be replaced anyway.

I have never experienced a sensor ring that bad, but I can imagine that the PCM/ Crankshaft Position Sensor are struggling to find the correct crankshaft position.

The Crankshaft Position Sensor itself seems to be functional because it is registering engine RPM during cranking.

3 hours ago, JW1982 said:

Well, that sensor ring inside the pulley does definitely not look good and considering the damage it should be replaced anyway.

I have never experienced a sensor ring that bad, but I can imagine that the PCM/ Crankshaft Position Sensor are struggling to find the correct crankshaft position.

The Crankshaft Position Sensor itself seems to be functional because it is registering engine RPM during cranking.

Do you think this damaged ring can also be the reason why the camshafts position sensors are not changing values? I can see the camshafts rotating but the values (as can see in the video) do not change during the ignition attempts..

As far as I know the camshaft position sensors show the position of the variable valve timing. I suspect that this is shown in degrees. It is perfectly normal for the camshaft position sensors to show a fixed value during cranking. The variable valve timing is only active when the engine is running and above a certain RPM threshold.


But looking at the video again I notice that the vehicle is shown as a Volvo. In the initial post you mentioned that it is a JTJA engine which is a specific version of the 1.6 EcoBoost engine only used in the Fiesta ST. This specific engine code has not been used in any other Ford model.

Ford used the 1.6 EcoBoost in several different Ford models where virtually each model has its own engine code. When the 1.6 EcoBoost was introduced, it was far from perfect. During a relatively small production period (2011 --> 2014) the 1.6 EcoBoost received several technical changes. At some point even the complete design of the cylinder head was changed. Because of the technical changes there are basically several different versions of the 1.6 EcoBoost that are not compatible. Many parts that are specific to the earlier designs have become obsolete/no longer available.  Therefore it is extremely important to know the exact engine code and what vehicle the engine is installed in.

21 minutes ago, JW1982 said:

As far as I know the camshaft position sensors show the position of the variable valve timing. I suspect that this is shown in degrees. It is perfectly normal for the camshaft position sensors to show a fixed value during cranking. The variable valve timing is only active when the engine is running and above a certain RPM threshold.


But looking at the video again I notice that the vehicle is shown as a Volvo. In the initial post you mentioned that it is a JTJA engine which is a specific version of the 1.6 EcoBoost engine only used in the Fiesta ST. This specific engine code has not been used in any other Ford model.

Ford used the 1.6 EcoBoost in several different Ford models where virtually each model has its own engine code. When the 1.6 EcoBoost was introduced, it was far from perfect. During a relatively small production period (2011 --> 2014) the 1.6 EcoBoost received several technical changes. At some point even the complete design of the cylinder head was changed. Because of the technical changes there are basically several different versions of the 1.6 EcoBoost that are not compatible. Many parts that are specific to the earlier designs have become obsolete/no longer available.  Therefore it is extremely important to know the exact engine code and what vehicle the engine is installed in.

You are correct, this is Volvo s60 2013. In these years Volvo partnered Ford, thus the engines in these Volvos are pure Ford engines.

My engine is the exact same as in Ford Fiesta ST. For volvo, the engine code is B4164T, for Ford, the engine code is JTJA.

Information and brand-experts are much more available for Ford rather then Volvo.

Due to the above mentioned, I seek help through Ford-knowing people, instead of asking in Volvo forums.

As I already said, due to the various changes during production there are basically quite a lot of variations of the 1.6 EcoBoost. Each Ford model has a different engine code to begin with and In many cases the more major changes also resulted in a change of engine code. The JTJA engine is quite a specific version of the 1.6 EcoBoost. So it is impossible to say that the Volvo B4164T engine is 100% identical to the Ford JTJA engine.

From experience I know that Volvo did use the bare 1.6 EcoBoost engine but on most models they implemented their own wiring, sensors, ECU and software. The Volvo B4164T engine may be mechanically identical to one of Fords versions of the 1.6 EcoBoost but electronically and diagnostics are usually a different story.

UPDATE:

In the end I solved the problem, so I wanted to post an update in case it helps someone in the future.

I managed to get a used crank pulley, installed it, and redid the timing. After that, the engine started and now it runs smoothly and sounds great.

My conclusion is that the "window" in the metal ring on the crank pulley is actually the signal reference for the crank position sensor. That signal is critical because the ECU uses it to determine engine position and timing. Since that window was damaged, the engine would not start.

So in my case, it was not just a normal timing issue — the crank pulley signal window itself was part of the problem.